Feasibility Study on Reference Material Preparation

Artificial rainwater solutions enriched with trimethyllead were prepared and diluted to obtain solutions containing three different levels 50 ng L , 500 ng L and 5 pg L [120]. These solutions were stored at room temperature and — 20°C. The composition of the artificial rainwater samples simulated the composition of real samples (addition of NH , Ca , Mg , Na , Cl , 

N03 and HsO ). The pH of the solutions upon storage was 3.84. The stability was studied during six months with determinations performed every month. The results showed that the decomposition of trimethyllead was most 

---